ABSTRACT
PURPOSE: Despite improved surgical techniques, pulmonary regurgitation is a common postoperative sequelae in patients with tetralogy of Fallot. Pulmonary regurgitation may induce deterioration of right ventricular performance, right ventricular dilatation and ventricular arrhythmia. The evaluation of the clinical significance of pulmonary regurgitation in postoperative tetralogy of Fallot has been troublesome since there was no technique that could accurately quantitate volume of pulmonary flow. Magnetic resonance imaging (MRI) with velocity mapping provided data on the volumetric quantitation of pulmonary regurgitation. The purpose of this present study was to assess right ventricular function and the severity of pulmonary regurgitation after surgical correction of tetralogy of Fallot by echocardiography and MRI. METHODS: Echocardiography and MRI were performed on nine patients with total surgical correction of tetralogy of Fallot. Quantitative volumetric assessment of pulmonary reguritation and right ventricular function was done. RESULTS: The pulmonary regurgitant volume was similar between echocardiography and MRI, and the pulmonary velocity was significantly larger by MRI in comparison with echocardiography. Right ventricular end-diastolic volume and stroke volume were similar in both two methods, but end-systolic volume was significantly larger by MRI in comparison to echocardiography. Pulmonary regurgitant volume was positively correlated with right ventricular end-systolic volume, end-diastolic volume and stroke volume. Each parameter (pulmonic velocity, pulmonary regurgitant volume, right ventricular end-diastolic volume, end-systolic volume, stroke volume) was significantly correlated linearly between echocardiography and MRI. CONCLUSION: Cine MRI with velocity mapping is an accurate method for the noninvasive, volumetric quantitation of pulmonary regurgitation after surgical correction of tetralogy of Fallot.